The present invention relates to a coupling device for power-operated machines for agricultural use or the like, and to a power-operated machine that includes the device.
As is known, there are many types of power-operated machines for agricultural use, or road works or for building yards, which are conceived to be applied to engines, which have both the task of moving them and the task of providing them with the necessary actuation power.
Generally, the power-operated machines are frontally connected to the arm of a mechanical shovel or to the front three-point hitch of a tractor and have to adapt to any unevenness of the ground, without being damaged and without compromising the result of the operations for which they are intended.
In this regard, some power-operated machines are provided with hitch and suspension devices that allow them in some way to adapt to undulations of the ground.
NL1029929 discloses a front trailed linkage for hitching a mower to a tractor, having a machine and support frames connected by pivoting support arms which allow a side shift of the mower around obstacles.
DE202007011631 discloses a coupling device for agricultural operating machines having an oscillating frame removably connected to a coupling unit of an engine and a mobile connecting means adapted to maintain the working plane of the operating machine parallel to the ground.
However, the prior art devices may work rather well with relatively long and gentle sloping paths but show their limitations when the sloping portions shorten to the point of affecting only the working plane of the power-operated machine or only the resting plane of the wheels or tracks of the engine.
Those problems become even more evident when the undulations of the ground tend to tilt the machines laterally.
The above problems arise mainly from the fact that power-operated machines equipped with the conventional coupling systems substantially tend to follow the alignment variations of the engines that carry them and are therefore forced to move substantially integrally with them.
In addition to this, it should also be noted that in the case of some specific power-operated machines, such as for example shredders, the conventional coupling systems may cause jamming of the front part of the machines, with consequent possible damage both to the ground and to the machines themselves.